[amtwo]

What does this change?

Changes the standard dbo.TimeZones.DisplayName column to nvarchar(128). The table script also upgrades existing built-in character columns to Unicode while preserving their current capacity (minimum 128 characters). The new contribution guidance explains why schema fixes must account for existing installations.

Related issue

Closes #22

Coding agent & Review agent disclosure

Coding agent details:

--Cody 🤖

Adversarial review details

• Adversarial review agent(s), provider/model, and reasoning effort (if applicable): Separate reviewer agent; model and reasoning effort unavailable.
• Reviewer/review approach and summary: Separate adversarial review of the complete final diff, migration behavior, installer import order, and the new contribution guidance. Searched repository references for dependent timezone data variables, parameters, and staging definitions.
• Findings resolved or left open (with reason): Findings about existing tables, wider varchar columns, and alias types were addressed. The final review found no actionable findings.
• Review had zero findings
• All findings were reconciled with high confidence

How did you test it?

• Checks performed: Compared the remote branch with current main; only CONTRIBUTING.md and tables/dbo.TimeZones.sql change. Confirmed the standard nvarchar(128) definition, capacity-preserving migration paths, alias-type guard, nullability preservation, and no trailing whitespace in changed lines. Repository search found no other variable, parameter, or temporary table definitions needing a width change.
• SQL Server version / edition and isolated environment tested (if applicable): Not tested.
• Runtime verification not performed / limitations (if applicable): Runtime testing was unavailable. sqlcmd is not installed, and Docker engine access was denied after checking the repository's SQL Edge smoke-test guidance.
• Sample call and result (for behavior changes):

SELECT
    ColumnName = c.name,
    DataType = t.name,
    MaxLengthBytes = c.max_length
FROM sys.columns AS c
JOIN sys.types AS t
    ON t.user_type_id = c.user_type_id
WHERE c.object_id = OBJECT_ID(N'dbo.TimeZones')
    AND c.name = N'DisplayName';

-- Expected for the standard table: nvarchar, 256 bytes (128 characters).
-- Illustrative only; not executed against SQL Server.

Checklist

• Follows the conventions in CONTRIBUTING.md for the existing table-script pattern and new T-SQL
• One object per file, filename matches the object name
• The header comment block is filled in (this existing table file has no header block)
• Re-running behavior was reviewed statically; runtime verification is identified as not performed